The present invention concerns a device for the heating of a liquid in a beverage machine.
It is already known to have a liquid heating module for use in a hot beverage machine. The patent application WO 01/54551 in the name of the assignee concerns a liquid heating module for use in a hot beverage machine, which comprises a hollow tube of metallic material, a cylindrical insert, disposed inside the hollow tube, at least one electrical resistor on a first part of the outside of the tube for preheating liquid and at least one other electrical resistor on a second part of the outside of the tube for temperature adjustment of the liquid flowing through the tube. The problem with this solution is that the resistors work in parallel and therefore there is a high demand of energy, because said resistors add their energy requirements, which can reach high level, when a high increase of the liquid temperature is required.
The objective of the present invention is to have also a device for the heating of a liquid in a hot beverage machine, wherein the variation of demand of power is less important, wherein the target temperature of the liquid is reached quickly and wherein there is a fine adjustment of the liquid temperature at the moment of the arrival of said liquid on an extraction head or other.